The present invention relates to the field of home entertainment. More specifically, the present invention relates to a signal selector for a television set that allows the television to receive and display audio and audiovisual signals from a number of different sources such as a video cassette recorder, digital video disk player, cable television system, compact disk player, etc.
In the current field of home entertainment, the use of the basic television sets has expanded far beyond the reception of broadcast television programming. Television sets are now used to receive and display audiovisual or audio signals from a number of sources. For example, a video cassette recorder (xe2x80x9cVCRxe2x80x9d) uses a magnetic head to read an audiovisual signal recorded on a magnetic tape. This signal can be provided to the television set and displayed to allow the user to watch the recorded programming. Digital video disk (xe2x80x9cDVDxe2x80x9d) players perform the same function except that the programming is recorded on an optical disc and read optically by the DVD player.
Additionally, a television set may be connected to a cable television system to which the user has subscribed. Typically, a coaxial cable is connected between a wall outlet and the television set, or a set-top box connected to the television set. The cable network delivers an audiovisual signal to the television set that may carry dozens or even hundreds of channels of television programming that can be tuned and watched by the user.
Similarly, the television set may be connected to a satellite dish, either fixed or moveable, that receives a digital or analog signal via satellite. The audiovisual signal provided by the satellite dish, like the cable television signal, includes dozens or even hundreds of channels of television programming that can be tuned and watched by the user.
Additionally, the television may also receive an audiovisual signal using a conventional antenna, either mounted on the user""s roof, or provided at the user""s television set, e.g., a rabbit-ears antenna. The conventional antenna can provide an audiovisual signal to the television set that is received by over-the-air broadcast from local commercial television stations.
In an emerging application, a television set may also be used to surf the internet or receive e-mail. Access to the internet may be provided over the cable television system through a set-top box. Alternatively, the television set could receive audiovisual signals from the internet by being connected through a computer or dedicated electronic device to the internet via a modem and conventional public phone line.
A modern entertainment center may include a television set that receives an input signal from any or all of these sources. Consequently, current sophisticated television sets are being designed with a number of input ports or jacks to which various signal sources can be connected.
Where the television set has multiple ports for receiving audiovisual signals from a variety of signal sources, a button on the television set, or on the set""s remote control unit, typically allows the user to cycle through connection to the available signal input ports in order to select which of the input signals will be used and displayed by the television set. For example, the default may be to use whatever input signal is provided through a first connector. This connector may be designated xe2x80x9cTVxe2x80x9d and would typically be connected to a cable television system or a conventional antenna for receiving basic commercial television programming. Whenever the television set is turned on, the set begins displaying the audiovisual signal provided through the first xe2x80x9cTVxe2x80x9d connector.
The television set in this example, having other connectors for receiving audiovisual signals from other sources, may have, for example, a second connector designated as xe2x80x9cVideo 1xe2x80x9d to which a VCR is connected, a third connector designated as xe2x80x9cVideo 2xe2x80x9d to which a DVD player is connected, and a fourth connector designated as xe2x80x9cVideo 3xe2x80x9d to which a tuner for a satellite dish is connected.
If the user wishes to use a signal coming from a source other than the first default connector, xe2x80x9cTV,xe2x80x9d the user presses the signal selector button on the television or remote control unit. Conventionally, this will switch the signal being received and used by the television set to that of the second connector, xe2x80x9cVideo 1.xe2x80x9d Pressing the button again selects the signal from the third connector, xe2x80x9cVideo 2,xe2x80x9d and so on.
If the user has just turned on the television set, but wishes to access the satellite dish connected to the xe2x80x9cVideo 3xe2x80x9d connector, the user must press the selection button three times to move through xe2x80x9cVideo 1xe2x80x9d and xe2x80x9cVideo 2xe2x80x9d to xe2x80x9cVideo 3.xe2x80x9d This is true even if, for example, no VCR or DVD player are connected to the xe2x80x9cVideo 1xe2x80x9d and xe2x80x9cVideo 2xe2x80x9d connectors respectively as described above. This can be frustrating to the user.
Additionally, the user must remember which signal source, i.e. VCR, DVD player, satellite dish, etc., is connected to which connector, i.e. xe2x80x9cVideo 1,xe2x80x9d xe2x80x9cVideo 2,xe2x80x9d xe2x80x9cVideo 3,xe2x80x9d etc. Again, this can be frustrating to the user.
Consequently, there is a need in the art for a means and method of managing the various input signal sources to a television set to more readily and rapidly allow the user to identify and select the desired and active input signal source.
It is an object of the present invention to meet the above-described needs and others. Specifically, it is an object of the present invention to provide a means and method of managing the various input signal sources to a television set to more readily and rapidly allow the user to identify and select a desired, active input signal source.
Additional objects, advantages and novel features of the invention will be set forth in the description which follows or may be learned by those skilled in the art through reading these materials or practicing the invention. The objects and advantages of the invention may be achieved through the means recited in the attached claims.
To achieve these stated and other objects, the present invention may be described as a system for managing a plurality of signal inputs to a television set. In a preferred embodiment, the system of the invention includes a plurality of audio and video signal inputs; a central processing unit; and an active signal detection unit that periodically monitors the signal inputs and signals the central processing unit to indicate which of the signal inputs is receiving an active signal. The active signal detection unit preferably includes a switch for connecting any of the signal inputs to the signal detection unit. The switch continuously cycles to sequentially connect each of the signal inputs in turn to the signal detection unit. Preferably, the signal detection unit includes a video signal detector and an audio signal detector.
The system may also include a primary tuner; and a selector switch controlled by the central processing unit for selectively connecting either the tuner or one of the signal inputs to a cathode ray tube of the television set. The selector switch is controlled by the central processing unit in response to a control signal from a user interface. To increase the ease with which a user can locate a desired input signal, the central processing unit controls the selector switch to automatically skip connections to signal inputs which are inactive when the user interface signals the central processing unit to change the connection state of the selector switch. After skipping the inactive signal inputs, the central processing unit may control the selector switch to connect to signal inputs which are inactive in response to continued actuation of the user interface device signaling a change of input signal source. This is done in anticipation of a signal being provided at the inactive input selected.
When the active signal detection unit detects a newly-active signal from one of the signal inputs, the central processing unit will be apprised of the new signal by the signal detection unit and may alert the user to receipt of the newly-active signal. The central processing unit may alert the user to receipt of the newly-active signal with an audio alert through a speaker of the television set or through a visual alert displayed on the cathode ray tube of the television set.
The central processing unit may also control the selector switch to cycle sequentially to connect the tuner and each active signal input to a video processing circuit. The video processing circuit then prepares a representative frame of each input signal. The representative frames are displayed on the cathode ray tube to generate a visual index of the active input signals. Preferably, the central processing unit repeatedly cycles the selector switch among the tuner and the active signal inputs to refresh the representative frames prepared by the video processing circuit.
The system of the present invention may also include a second selector switch controlled by the central processing unit for selectively connecting either the tuner or one of the signal inputs to a video processing circuit. The video processing circuit adds a secondary input signal received through the second selector switch to a primary input signal received through the first selector switch to create a picture-in-picture display on the cathode ray tube. The picture-in-picture mode can be further augmented by including a second tuner having an output that is provided to the second selector switch.
The central processing unit may automatically connect the second selector switch to a newly-active signal input, as indicated by the active signal detection unit. This provides the newly-active signal in a secondary picture window of the picture-in-picture display to alert a user to the newly-active signal input.
The system of the present invention can also be adapted to a digital television system in which a plurality of digital audiovisual signal inputs are provided. Each digital audiovisual signal input provides a data transport stream and an error flag signal to a transport parser/demultiplexer. The transport parser/demultiplexer provides the error flag signals to the central processing unit so that the central processing unit can determine which of the digital audio visual signal inputs is receiving an active signal. Consequently, the central processing unit controls the transport parser/demultiplexer and a selector switch that selects among the plurality of audio and video signal inputs to connect only active signal inputs to the cathode ray tube of the television set when switching signal sources in response to operation of a user interface.
The present invention also encompasses the methods of implementing and operating the system described above. For example, the present invention expressly includes a method of managing a plurality of audio and video signal inputs to a television set with a central processing unit by periodically monitoring the signal inputs with an active signal detection unit that signals the central processing unit to indicate which of the signal inputs is receiving an active signal so that the central processing unit can manage the various signal inputs accordingly.